The other day, my husband was in the middle of aArticle reviewing the effectiveness of the MegaLife battery (lithium-ion battery) in the 964.He wrote about the 981 Boxster GTS with the MegaLife battery, and now he has written a review of it as well. Please take a look if you like.

Lightweight mega-life battery

The battery installed again will also be the MV-072 type.The Boxster's battery is mounted in the same position as the 991 and other models, just in front of the windshield.The center of gravity is placed very high, though inside the front axle, so the effect on the center of gravity height is not small.

As before.Super Autobacs Sunshine KOBEThe replacement work is done at Talking to the person in charge of theAlready 5 Porsche owners who saw my last blog post have already come to exchange their Porsches.Looks like (laughter)

This time I held the battery by hand before replacing it, to get a feel for how heavy it was.After all, MegaLife batteries are light.It weighs only a little more than 7 kg, so it can be lifted normally with one hand. The lead-acid battery, on the other hand, weighs about 20 kg, so it is painful to lift with one hand. You have to use both hands to lift it up with a lot of effort. Depending on the position of the body, it is heavy enough to be painful to the waist.

Considering that such a heavy object at the top is so light, it is only natural that it would affect driving performance.Moreover, the cost is about 110,000 yen, and it is more than a dozen kilos lighter.

The Weissach package for the 991 GT3RS costs about 3.2 million yen and is 18 kg lighter with a carbon hood and titanium roll cage. Then think about it.It can be said that the weight reduction is quite cost-effective.

What are your impressions of the city?

After replacing the battery, I immediately started driving and, as with the 964, the steering felt different from the moment I left the store. To describe the steering feel with the word "light" is a bit of an understatement.I prefer to say that it feels like the steering wheel has lost its friction.Anyway, the steering wheel seems to turn smoothly.

The front ground feel is less like a weight pressing down on you and more like a Porsche with PCCB brakes. The nimble, well-defined up-and-down movement of the foot is evident even just over undulations in the city. As for ride quality, there's nothing particularly bouncy about it.In fact, I even feel the feeling that my legs have become more supple.

My wife also rode in town after this, and she said, "I can tell it's lighter! And the acceleration has improved.said, so the high and consistent discharge rate unique to lithium-ion batteries may have affected engine power in no small way.

When I ride consciously after being told so, too, it is true.The mid-range acceleration in 3rd and 4th gear seems slightly more powerful.

How has the movement in winding down changed?

We moved the location to Ashiu to check the movement on the winding road.
First of all, when taking a normal curve, the steering is still smooth, making it easier to understand the road surface conditions and the direction and feel of the tires.

besidesIn situations where the road surface is a bit wavy, it is much more stable than before.I think. This is probably due to the increased tracking of the front suspension. The effect of up-and-down movement has been reduced, and the car seems to be able to turn corners more stably.

On good road surfaces, I don't notice much difference in the way the curves turn when going uphill, but I do notice a difference in the way the curves turn when going downhill.It is very different on flat roads and downhill corners.This may be due in part to the fact that the Boxster is mid-ship.

The tendency to understeer on downhill slopes is reduced and the car turns neutrally.I wouldn't go so far as to say that it is as easy to drive downhill as the 911, but the biggest difference this time, after replacing the battery, is the stability of this downhill driving.

What are your impressions on the highway?

I also drove a little on the highway, but I don't think there is any significant difference in handling feel because the amount of steering is so small to begin with.

On the other hand, changes can be seen in terms of ride quality rather than ride comfort. Specifically, theThe front end feels lighter than before, yet somehow the sense of security and stability feels stronger.It is difficult to describe this feeling in words, but I am certain that it is positive in any case.

By the way, I had no idea with the 964, and there wasn't that kind of change.In the case of the Boxster, when cruising on the highway with the top closed, a high-frequency sound like an alternator noise is faintly heard, just slightly, in response to the engine speed.It is now. This is so loud that some people (depending on their age) may not be able to hear it, and when the top is open, it is audible, although at a level that is completely unrecognizable.

With the change in voltage and current, this area may have a slight effect on the audio and speakers. I would like to do some more research on this area to see where the sound is coming from.

[2021/6/7 Postscript
Regarding the alternator noise-like sound, it was subsequently determined that

• It's not coming from the speakers, it's coming from somewhere behind the dashboard (or so it seems).
  I then pulled the fuse on the amp and ran it, and the sound completely disappeared, so it turned out to be coming from the speaker.
• It is not audible when riding normally in normal mode.
• On the other hand, when the car is driven in Sport or Sport Plus for sport driving, the engine control changes and the idling rpm increases. The battery voltage then rises from around 13.2V to around 14.5V. While that voltage is rising, a sound is heard in response to the engine speed. (During this time, for a few minutes)
• When the voltage is constant around 14.5V, the sound disappears and is not heard. On the other hand, in normal mode, the voltage always stays around 13.2V, but again, it is not heard.

This seems to be the case. This suggests that it is likely thatElectrical noise seems to be audible at times when the battery is being actively charged.. This period lasts only a few minutes and is not noticeable if you are concentrating on driving, playing music, or have the top open, so it is not a personal concern, but those who are nervous should be aware of this.

[2022/2/6 postscript]
This noise problem has been completely resolved.

• The cause of noise isTurned out to be a genuine amplifier (or wiring from Clarion Navi to the amplifier)The following is a list of the most common problems with the "C" in the "C" column.
• If you connect the wiring from the navigation system to the amplifier directly to the speaker by bypassing the amplifier, the noise will disappear completely.

Overall Evaluation of MegaLife Battery

As with 964, I find it quite effective. Of course, each person has different senses and feels it to a different degree, but I think many people can feel the difference, as my wife can tell as well as I can.

Although very expensive when considered as a battery, theConsidering its longevity and the effect from its light weight, it is a very cost-effective tuningI think it is a good idea. If you are thinking of replacing your battery, you may want to consider this battery as well.